In general, an organic light emitting phenomenon refers to a phenomenon in which electronic energy is converted into light energy by means of an organic material. An organic electronic element utilizing the organic light emitting phenomenon usually has a structure including an anode, a cathode, and an organic material layer interposed therebetween. Here, in many cases, the organic material layer may have a multilayered structure including multiple layers made of different materials in order to improve the efficiency and stability of an organic electronic element, and for example, may include a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer, and the like.
A material used as an organic material layer in an organic electronic element may be classified into a light emitting material and a charge transport material, for example, a hole injection material, a hole transport material, an electron transport material, an electron injection material, and the like according to its function.
It is required to develop a hole injection layer material that retards penetration/diffusion of metal oxides from an anode electrode (ITO) into an organic layer, which is one cause for the shortened lifetime of an organic electronic element, and has stability against Joule heat generated during the operation of an organic electronic element, that is, a high glass transition temperature. Also, it has been reported that a low glass transition temperature of a hole transport layer material has a great effect on the lifetime of an organic electronic element because the uniformity of a thin film surface collapses during the operation of the element. In general, deposition is a main method of forming an OLED, and thus there is an actual need to develop a material that is durable to such a deposition method, that is, a highly heat-resistant material.
That is, in order to allow an organic electronic element to fully exhibit the above-mentioned excellent features, it should be prerequisite to support a material constituting an organic material layer in the element, for example, a hole injection material, a hole transport material, a light emitting material, an electron transport material, an electron injection material, or the like, by a stable and efficient material. However, such a stable and efficient organic material layer material for an organic electronic element has not yet been fully developed. Accordingly, there is a continuous need to develop new materials for an organic material layer.